This clinical trial is focused on studying a type of blood cancer called Acute Myeloid Leukemia (AML). The study is testing a new treatment approach for adults whose AML has returned or did not respond to initial treatment. The treatment being studied involves a combination of two drugs: Liposomal Annamycin and Cytarabine. Liposomal Annamycin is a form of chemotherapy that is designed to target cancer cells more effectively, while Cytarabine is a well-known chemotherapy drug used to treat AML. The study will compare this combination to a placebo combined with Cytarabine to see which is more effective as a second-line treatment.

The purpose of the study is to find the best dose of Liposomal Annamycin when used with Cytarabine and to confirm if this combination works better than the placebo with Cytarabine. Participants will receive the treatment through an infusion, which means the medication is given directly into the bloodstream. The study is divided into two parts. In the first part, researchers will determine the optimal dose of Liposomal Annamycin. In the second part, they will test this dose against the placebo to see if it improves the rate of complete remission, which means the cancer is no longer detectable after one cycle of treatment.

Participants will be monitored closely throughout the study to assess the safety and tolerability of the treatment. The study will also look at how long the remission lasts, overall survival rates, and the possibility of undergoing a bone marrow transplant after achieving remission. The trial aims to provide valuable information that could lead to better treatment options for people with refractory or relapsed AML.